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<table width="100%" summary="page for SpaceShuttle"><tr><td>SpaceShuttle</td><td align="right">R Documentation</td></tr></table>

<h2>Space Shuttle O-ring Failures</h2>

<h3>Description</h3>


<p>Data from Dalal et al. (1989) about O-ring failures in the NASA space
shuttle program.  The damage index comes from a discussion of the data
by Tufte (1997).
</p>


<h3>Usage</h3>

<pre>
data("SpaceShuttle")
</pre>


<h3>Format</h3>


<p>A data frame with 24 observations and 6 variables.
</p>

<dl>
<dt>FlightNumber</dt><dd><p>Number of space shuttle flight.</p>
</dd>
<dt>Temperature</dt><dd><p>temperature during start (in degrees F).</p>
</dd>
<dt>Pressure</dt><dd><p>pressure.</p>
</dd>
<dt>Fail</dt><dd><p>did any O-ring failures occur? (no, yes).</p>
</dd>
<dt>nFailures</dt><dd><p>how many (of six) 0-rings failed?.</p>
</dd>
<dt>Damage</dt><dd><p>damage index.</p>
</dd>
</dl>



<h3>Source</h3>


<p>Michael Friendly (2000),
Visualizing Categorical Data:
<a href="http://euclid.psych.yorku.ca/ftp/sas/vcd/catdata/orings.sas">http://euclid.psych.yorku.ca/ftp/sas/vcd/catdata/orings.sas</a>
</p>


<h3>References</h3>


<p>S. Dalal, E. B. Fowlkes, B. Hoadly (1989),
Risk analysis of the space shuttle: Pre-Challenger prediction of
failure,
<EM>Journal of the American Statistical Association</EM>,
<B>84</B>, 945&ndash;957.
</p>
<p>E. R. Tufte (1997),
<EM>Visual Explanations: Images and Quantities, Evidence and
Narrative</EM>.
Graphics Press, Cheshire, CT. 
</p>
<p>M. Friendly (2000),
<EM>Visualizing Categorical Data</EM>.
SAS Institute, Cary, NC.
</p>


<h3>Examples</h3>

<pre>
data("SpaceShuttle")
plot(nFailures/6 ~ Temperature, data = SpaceShuttle,
     xlim = c(30, 81), ylim = c(0,1),
     main = "NASA Space Shuttle O-Ring Failures",
     ylab = "Estimated failure probability",
     pch = 19, col = 4)
fm &lt;- glm(cbind(nFailures, 6 - nFailures) ~ Temperature,
          data = SpaceShuttle,
          family = binomial)
lines(30 : 81,
      predict(fm, data.frame(Temperature = 30 : 81), type = "re"),
      lwd = 2)
abline(v = 31, lty = 3)
</pre>


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